The best teaching methods include physical demonstrations of the subject-matter being taught. When the new knowledge can be seen, heard or touched, it is easier to assimilate and to be retained by students. If the demonstration apparatus also stimulates the imagination, the new knowledge being taught is more effectively absorbed and remembered.
The properties of gases and fluid mechanics in particular are difficult subjects to teach because gases are invisible and impalpable. Other that hot air balloons, which are impractical devices for use in a classroom environment, teaching methods on gas properties are limited to chalk and blackboard explanations.
It is believed that there is a need in the education system for an apparatus that can be used to demonstrate gas densities, buoyancy and the diffusion rates of different gases. It is believed that there is a need for a classroom or lecture hall size educational device that can be used to visualize the presence of a gas therein, and to feel the buoyancy force exerted by that gas on a floating balloon.